/**
 * User数据模型模块
 */

//导入SQLite3模块
const sqlite3 = require("sqlite3").verbose();
//导入工具模块
const util = require("../../common/util");
//导入配置模块
const config = require("../../common/config");

class UserDB {
    /**
  * @constructor
  * @private
  */
    constructor() {
        this.dbFile = config.dbFile;
        this.instance = null;
        this.db = null;
        this.register = this.add;
    }

    /**
  * 创建UserDB对象
  * @returns {UserDB} UserDB实例
  */
    static getInstance() {
        if (!this.instance) {
            this.instance = new UserDB();
        }
        return this.instance;
    }

    /**
     * 连接数据库
     * @returns {Promise}
     */
    connect() {
        return new Promise((resolve, reject) => {
            this.db = new sqlite3.Database(this.dbFile, (err) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve("connect ok.");
                }
            });
        });
    }
    /**
     * 关闭数据库
     * @returns  {Promise}
     */
    close() {
        return new Promise((resolve, reject) => {
            this.db.close((err) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve("close ok.");
                }
            });
        });
    }

    /**
     * 获取指定ID的用户信息
     * @param {Number} userId 用户ID
     * @returns  {Promise}
     */
    find(userId) {
        return new Promise((resolve, reject) => {
            let sql = "SELECT * FROM users WHERE id = ?";
            let params = [userId];
            this.db.get(sql, params, (err, result) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(result);
                }
            });
        });
    }

    /**
     * 获取用户信息列表
     * @param {Number} limit 数量
     * @param {Number} offset 开始
     * @returns  {Promise}
     */
    findAll(limit = -1, offset = -1) {
        return new Promise((resolve, reject) => {
            let sql = "";
            let params = [];
            if (limit === -1) {
                sql = "SELECT * FROM users ORDER BY id";
            } else if (offset === -1) {
                sql = "SELECT * FROM users ORDER BY id LIMIT ?";
                params[0] = limit;
            } else {
                sql = "SELECT * FROM users ORDER BY id LIMIT ? OFFSET ?";
                params[0] = limit;
                params[1] = offset;
            }
            this.db.all(sql, params, (err, result) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(result);
                }
            });
        });
    }

    /**
     * 新增用户
     * @param {Object} user 用户数据
     * @returns  {Promise}
     */
    add(user) {
        return new Promise((resolve, reject) => {
            let sql = `INSERT INTO users (
                username, password, nickname, truename, avatar,
                role, last_login_time, last_login_ip, created_time, created_ip, 
                updated_time
              ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`;
            let params = [
                user.username,
                user.password,
                user.nickname,
                user.truename,
                user.avatar,
                user.role,
                user.lastLoginTime,
                user.lastLoginIP,
                user.createdTime,
                user.createdIP,
                user.updatedTime,
            ];

            this.db.run(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    util.log(this);
                    resolve(this.lastID); //插入的数据的自增ID
                }
            });
        });
    }

    /**
   * 修改用户个人信息
   * @param {Object} user 用户数据
   * @returns  {Promise}
   */
    changeInfo(id, info) {
        return new Promise((resolve, reject) => {
            let sql = `UPDATE users SET nickname = ?, truename = ?, avatar = ? WHERE id = ?;`;
            let params = [
                info.nickname,
                info.truename,
                info.avatar,
                id,
            ];

            this.db.run(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(this.changes); //影响的记录数
                }
            });
        });
    }

    /**
     * 修改用户
     * @param {Object} user 用户数据
     * @returns  {Promise}
     */
    update(user) {
        return new Promise((resolve, reject) => {
            let sql = `UPDATE users SET username = ?, password = ?, nickname = ?, truename = ?, avatar = ?, role = ?, updated_time = ? WHERE id = ?;`;
            let params = [
                user.username,
                user.password,
                user.nickname,
                user.truename,
                user.avatar,
                user.role,
                user.updatedTime,
                user.id,
            ];

            this.db.run(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(this.changes); //影响的记录数
                }
            });
        });
    }

    /**
     * 删除用户
     * @param {Number} userId 用户ID
     * @returns  {Promise}
     */
    remove(userId) {
        return new Promise((resolve, reject) => {
            let sql = "DELETE FROM users WHERE id = ?";
            let params = [userId];
            this.db.run(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(this.changes); //影响的记录数
                }
            });
        });
    }

    /**
    * 获取用户数量
    * @returns  {Promise}
    */
    getCount() {
        return new Promise((resolve, reject) => {
            let sql = "SELECT count(1) AS total FROM users";
            let params = [];
            this.db.get(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(result.total);
                }
            });
        });
    }

    /**
 * 搜索用户
 * @param {String} q 查询关键字
 * @param {Number} limit 数量
 * @param {Number} offset 偏移
 * @returns {Promise} 
 */
    search(q, limit = -1, offset = -1) {
        return new Promise((resolve, reject) => {
            let sql = "";
            q = `%${q}%`;
            let params = [q, q, q];
            if (limit === -1) {
                sql = "SELECT * FROM users WHERE username LIKE ? OR nickname LIKE ? OR truename = ?";
            } else if (offset === -1) {
                sql = "SELECT * FROM users WHERE username LIKE ? OR nickname LIKE ? OR truename = ? LIMIT ?";
                params.push(limit);
            } else {
                sql = "SELECT * FROM users  WHERE username LIKE ? OR nickname LIKE ? OR truename = ? LIMIT ? OFFSET ?";
                params.push(limit);
                params.push(offset);
            }
            this.db.all(sql, params, (err, result) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(result);
                }
            });
        });
    }

    /**
   * 获取指定ID的用户信息
   * @param {String} username 用户名
   * @param {String} password 密码
   * @returns  {Promise}
   */
    login(username, password) {
        return new Promise((resolve, reject) => {
            let sql = "SELECT * FROM users WHERE username = ? AND password = ?";
            let params = [username, password];
            this.db.get(sql, params, (err, result) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(result);
                }
            });
        });
    }

    /**
     * 更新用户登录相关数据
     * @param {String} username 用户名
     * @param {Object} lastLogin 登录状态对象 
     * @returns {Promise}
     */
    touch(username, lastLogin) {
        return new Promise((resolve, reject) => {
            let sql = `UPDATE users SET last_login_time = ? , last_login_ip = ?, login_count = login_count + 1 WHERE username = ?`;
            let params = [lastLogin.time, lastLogin.ip, username];
            this.db.run(sql, params, (err, result) => {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(this.changes);
                }
            });
        });

    }

    /**
   * 修改用户密码
   * @param {Number} id 用户id
   * @param {String} password 用户密码
   * @returns  {Promise}
   */
    changePassword(id, password) {
        return new Promise((resolve, reject) => {
            let sql = `UPDATE users SET password = ? WHERE id = ?;`;
            let params = [password, id];

            this.db.run(sql, params, function (err, result) {
                if (err) {
                    util.err(err);
                    reject(err);
                } else {
                    resolve(this.changes); //影响的记录数
                }
            });
        });
    }

    


}

module.exports = UserDB;